U.S. patent application number 12/362747 was filed with the patent office on 2010-08-05 for variable speed transamission.
Invention is credited to John Coleman, Tom Joseph Slater.
Application Number | 20100192532 12/362747 |
Document ID | / |
Family ID | 42396569 |
Filed Date | 2010-08-05 |
United States Patent
Application |
20100192532 |
Kind Code |
A1 |
Slater; Tom Joseph ; et
al. |
August 5, 2010 |
Variable Speed Transamission
Abstract
A grass treatment device is provided, which comprises a motor
configured to provide a power, a grass treatment tool configured to
interact with and treat a grass surface, a drive mechanism
configured to propel the device relative to the grass surface and a
transmission operably positioned between the motor, the tool and
the drive mechanism. The transmission is configured to transmit
power from the motor independently to the tool and to the drive
mechanism. The transmission is further configured to transform a
constant output from the motor into independent variable powering
of the tool and the drive mechanism.
Inventors: |
Slater; Tom Joseph;
(Sheffield, GB) ; Coleman; John; (Sheffield,
GB) |
Correspondence
Address: |
MESCHKOW & GRESHAM, P.L.C.
7250 NORTH SIXTEENTH STREET, SUITE 318
PHOENIX
AZ
85020-5279
US
|
Family ID: |
42396569 |
Appl. No.: |
12/362747 |
Filed: |
January 30, 2009 |
Current U.S.
Class: |
56/11.5 ;
56/11.1; 56/11.4; 74/665F |
Current CPC
Class: |
A01D 69/06 20130101;
A01B 33/082 20130101; A01B 33/028 20130101; Y10T 74/19074 20150115;
A01D 34/62 20130101 |
Class at
Publication: |
56/11.5 ;
56/11.4; 56/11.1; 74/665.F |
International
Class: |
A01D 69/00 20060101
A01D069/00; A01D 69/06 20060101 A01D069/06; A01D 69/08 20060101
A01D069/08; F16H 37/06 20060101 F16H037/06 |
Claims
1. A grass treatment device, comprising: a motor configured to
provide a power; a grass treatment tool configured to interact with
and treat a grass surface; a drive mechanism configured to propel
the device relative to the grass surface; a transmission operably
positioned between the motor, the tool and the drive mechanism,
configured to transmit power from the motor independently to the
tool and to the drive mechanism; wherein the transmission is
further configured to transform a constant output from the motor
into independent variable powering of the tool and the drive
mechanism.
2. A grass treatment device according to claim 1, wherein the drive
mechanism configured to propel the treatment device and the grass
treatment are powered by respective output shafts of the
transmission.
3. A grass treatment device according to claim 2, wherein the
output shafts respectively powering the drive mechanism and the
grass treatment tool are driven with respective transmission
ratios.
4. A grass treatment device according to claim 1, wherein the
output shafts respectively powering the drive mechanism and the
grass treatment tool are driven with the same transmission
ratio.
5. A grass treatment device according to claim 1, wherein the
transmission is capable of providing a continuously variable
output.
6. A grass treatment device according to claim 5, wherein the
transmission comprises a continuously variable transmission.
7. A grass treatment device according to claim 5, wherein the
transmission comprises an infinitely variable transmission.
8. A grass treatment device according to claim 1, wherein the
transmission is capable of powering either the grass treatment tool
or the drive mechanism at a respective plurality of speed
settings.
9. A grass treatment device according to claim 8, wherein the
transmission comprises a speed selector mechanism.
10. A grass treatment device according to claim 1, wherein the
transmission is capable of independently powering the grass
treatment tool and the drive mechanism at a plurality of respective
speed settings.
11. A grass treatment device according to claim 10, wherein the
transmission comprises first and second speed selector mechanisms,
wherein selection of a speed setting for the grass treatment tool
is effected with the first speed selector mechanism and selection
of a speed setting for the drive mechanism is effected with the
second speed selector mechanism.
12. A grass treatment device according to claim 11, wherein each of
the first and second speed selector mechanisms comprises a
transmission adjusting lever, the displacement of which
proportionally increases or decreases the transmission ratio.
13. A grass treatment device according to claim 12, wherein
displacement of each transmission adjusting lever is effected by a
lever adjustment assembly, comprising a transmission adjusting
lever engaging shaft, a shaft height adjusting knob and a shaft
bracket affixed to the transmission.
14. A grass treatment device according to claim 13, wherein a
rotation of the shaft height adjusting knob effects either an
upward or a downward translation of the transmission adjusting
lever engaging shaft, relative to the combination of the knob and
bracket.
15. A grass treatment device according to claim 13, wherein a
portion of the transmission adjusting lever engaging shaft
protrudes from an aperture in the adjusting knob and comprises
graduation means, to which the speed of the transmission output
shaft can be correlated.
16. A grass treatment device according to claim 12, further
comprising means to adjust the height of the transmission adjusting
lever engaging shaft by predetermined quantized amounts.
17. A grass treatment device according to claim 16, wherein the
means to adjust the height of the transmission adjusting lever
engaging shaft comprises a spring-biased ball and at least one
complementary depression between the knob and the bracket.
18. A grass treatment device according to claim 17, further
comprising a plurality of depressions.
19. A grass treatment device according to claim 1, wherein the
grass treatment device comprises a cassette system configured to
allow the introduction and removal of a plurality of various grass
treatment tools, each of which is configured to be operably
connected to the transmission.
20. A grass treatment device according to claim 19, wherein the
grass treatment tool is one selected from the group comprising a
vibratory roller; a thatchmaster; an ultra grooma; a scarifier; a
sarel roller cassette;a star spiker;a rotary brush and a true level
vibratory roller brush.
21. A grass treatment device according to claim 19, wherein the
cassette system comprises a first and a second roller configured to
contact a grass surface, wherein the treatment tool is positioned
between the first and the second roller.
22. A grass treatment device according to claim 1, wherein the
motor comprises an electrical motor.
23. A grass treatment device according to claim 1, wherein the
motor comprises an internal combustion motor.
24. A grass treatment device according to claim 1, wherein the
motor is connected to the transmission by a centrifugal clutch.
25. A grass treatment device, comprising: a motor configured to
provide a power; a grass treatment tool configured to interact with
and treat a grass surface; a drive mechanism configured to propel
the device relative to the grass surface; a transmission operably
positioned between the motor, the tool and the drive mechanism,
configured to transmit power from the motor independently to the
tool and to the drive mechanism; wherein the transmission is
further configured to transform a constant output from the motor
into independent variable powering of the tool and the drive
mechanism; and wherein the grass treatment device is selected from
the group comprising two-wheeled, four-wheeled and tracked
devices
26. A grass treatment device according to claim 25, wherein the
grass treatment device is selected from the group comprising
devices requiring the user to stand in close proximity thereto,
devices requiring the user to sit thereon and remote--controlled
devices.
27. A transmission for use with a grass treatment device, the
device comprising a motor configured to configured to provide
power; a grass treatment tool configured to interact with and treat
a grass surface; a drive mechanism configured to propel the device
relative to the grass surface; and the transmission; wherein the
transmission is operably positioned between the motor, the tool and
the drive mechanism, and is configured to transmit power from the
motor independently to the tool and to the drive mechanism; and the
transmission is further configured to transform a constant output
from the motor into independent variable powering of the tool and
the drive mechanism.
28. A transmission according to claim 27, wherein the drive
mechanism configured to propel the treatment device and the grass
treatment are powered by respective output shafts of the
transmission.
29. A transmission according to claim 28, wherein the output shafts
respectively powering the drive mechanism and the grass treatment
tool are driven with respective transmission ratios.
30. A transmission according to claim 27, wherein the output shafts
respectively powering the drive mechanism and the grass treatment
tool are driven with the same transmission ratio.
31. A transmission according to claim 27, wherein the transmission
is capable of providing a continuously variable output.
32. A transmission according to claim 31, wherein the transmission
comprises a continuously variable transmission.
33. A transmission according to claim 31, wherein the transmission
comprises an infinitely variable transmission.
34. A transmission according to claim 27, wherein the transmission
is capable of powering either the grass treatment tool or the drive
mechanism at a respective plurality of speed settings.
35. A transmission according to claim 34, wherein the transmission
comprises a speed selector mechanism.
36. A transmission according to claim 27, wherein the transmission
is capable of independently powering the grass treatment tool and
the drive mechanism at a plurality of respective speed
settings.
37. A transmission according to claim 36, wherein the transmission
comprises first and second speed selector mechanisms, wherein
selection of a speed setting for the grass treatment tool is
effected with the first speed selector mechanism and selection of a
speed setting for the drive mechanism is effected with the second
speed selector mechanism.
38. A transmission according to claim 37, wherein each of the first
and second speed selector mechanisms comprises a transmission
adjusting lever, the displacement of which proportionally increases
or decreases the transmission ratio.
39. A transmission according to claim 38, wherein displacement of
each transmission adjusting lever is effected by a lever adjustment
assembly, comprising a transmission adjusting lever engaging shaft,
a shaft height adjusting knob and a shaft bracket affixed to the
transmission.
40. A transmission according to claim 39, wherein a rotation of the
shaft height adjusting knob effects either an upward or a downward
translation of the transmission adjusting lever engaging shaft,
relative to the combination of the knob and bracket.
41. A transmission according to claim 39, wherein a portion of the
transmission adjusting lever engaging shaft protrudes from an
aperture in the adjusting knob and comprises graduation means, to
which the speed of the transmission output shaft can be
correlated.
42. A transmission according to claim 38, further comprising means
to adjust the height of the transmission adjusting lever engaging
shaft by predetermined quantized amounts.
43. A transmission according to claim 42, wherein the means to
adjust the height of the transmission adjusting lever engaging
shaft comprises a spring-biased ball and at least one complementary
depression between the knob and the bracket.
44. A kit of parts for a grass treatment device, comprising: a
motor configured to configured to provide power; a grass treatment
tool configured to interact with and treat a grass surface; a drive
mechanism configured to propel the device relative to the grass
surface; and a transmission operably positioned between the motor,
the tool and the drive mechanism, configured to transmit power from
the motor independently to the tool and to the drive mechanism;
wherein the transmission is further configured to transform a
constant output from the motor into independent variable powering
of the tool and the drive mechanism.
45. A method of independently powering a drive mechanism and a
grass treatment tool of a grass treatment device, the method
comprising the steps of: providing the device with the grass
treatment tool, the drive mechanism and a motor; providing the
device with a transmission operably positioned between the motor,
the tool and the drive mechanism, wherein the transmission is
configured to transform a constant output from the motor into
independent variable powering of the tool and the drive mechanism;
and transmitting power from the motor independently to the tool and
to the drive mechanism through the transmission.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a new type of transmission
for a turf or grass treatment apparatus such as a mower, the
transmission comprises a variable speed gearbox with at least two
gear ratios.
BACKGROUND TO THE INVENTION
[0002] Traditional hand operated grass treatment devices such as
mowers or greensrollers comprise a transmission or gearbox with a
single gear ratio as the treatment mechanism of the device, which
is driven by the gearbox, is fixed and therefore a single gear
ratio is sufficient to provide a preset speed or number of
revolutions per minute to the connected tool. The motor also
generally drives the device forward by powering wheel or other
structures and likewise generally only a single speed is required
to ensure, as far as possible, a uniform treatment regime.
[0003] An example of such a prior art grass treatment device is
disclosed in U.S. Pat. No. 6,200,066 (B1), wherein a self-propelled
vibratory greensroller is provided for smoothing a green, improving
ball roll distance and striping. The greensroller has a vibratory
roller and a power roller mounted in a frame with the vibratory
roller in front of and parallel to the power roller. A prime mover
mounted on the frame has a gear box with two power-take offs for
connection to first and second power trains. The first power train
includes a centrifugal clutch, which starts the vibratory roller
into vibration at some preselected engine speed. The second power
train includes a variable speed pulley, which provides infinite
ground speed control for the power roller.
[0004] Another example of such a prior art grass treatment device
is disclosed in GB 1237643 (A), wherein a two-speed chain and
sprocket gearbox is provided for driving the roller of a
power-operated lawn-mower. The chain and sprocket gearbox comprises
an electric or I.C. engine driven shaft, which drives through a
spring-engaged, manually-released dog clutch to a gear input shaft,
on which first and second sprockets are mounted freely and via a
one-way sprag clutch respectively. The sprockets are connected via
chains to a lay-shaft, which is in turn connected to the roller via
two further sprockets and a chain. In first (low) speed, the input
shaft drives through the one-way clutch to the first sprocket
driving the roller via chains, the second sprocket rotating freely
on the shaft. In second (high) speed, provided by axially sliding
the second sprocket into engagement with a dog-clutch peg on the
input via a manual gear selector and lever arm, the second sprocket
drives the roller via chains, the first sprocket overrunning on the
one-way sprag clutch.
[0005] The most important consideration and driving factor behind
the work of the greens keeper is to, insofar as possible, ensure
uniformity between all the different greens of a given golf course.
Most normally greens are measured using the distance a golf ball
travels across the green when it is hit with a pre-determined
quantity of force. The actual distance the ball travels on a
particular green is not something which green keepers seek to set
at a particular level, a more important consideration is that all
the different greens on a given course have, as far as possible,
identical properties.
[0006] Various tools exist to allow the greens keeper to alter the
properties of a particular green or other turf surface. A normal
approach a greens keeper could take is to add or remove material
from a green using a variety of different mechanical means and
introducing or attempting to remove various different materials.
For instance, often greens keeper will introduce sand into the
green in order to lighten the underlying soil in which the turf
rests.
[0007] This can be facilitated after the application of sand to a
surface using a vibratory roller which, through vibrations as its
name suggests, causes sand placed upon the surface of a green to
fall through the shoots of the green onto and into the soil
surface.
[0008] Alternatively, the mechanical manipulation of the green may
also be effected using, for instance, a groomer, which comprises a
number of substantially rigid and parallel blades that are
perpendicular to the shaft in which they rest and about which they
turn. The interaction of such a groomer with a grass surface can
physically mix the existing structure of the soil with any material
placed on top of it, for instance, sand, fertiliser or other
organic or inorganic materials.
[0009] At the present time, most prior art devices to assist the
greens keeper in such tasks are limited to a specific type of
treatment tool associated with a specific device. Further,
generally speaking the tool is also configured to move at a set
rate which can not be varied by a user, for instance the vibratory
roller disclosed in U.S. Pat. No. 6,200,066 (B1). Therefore, if
different treatment regimes are required upon different greens or
other areas of the golf course, it is often necessary for a greens
keeper to employ several devices, each of which is used to effect
one or more treatment regimes on different portions of the golf
course. This can result is significant costs, as each of these
machines needs to be maintained in good working order even though
it may only be used to treat a single or a small number of greens
at unpredictable intervals over its operating lifetime. A limited
number of prior art devices feature a system of interchangeable
treatment tools, which only partially overcomes the above problem,
because the speed of rotation of the tools is not configurable in
these devices, whereby their effctiveness is limited.
[0010] In addition, it is also possible that, in order to achieve a
specific treatment regime for a grass surface, a user may wish to
use a single type of treatment tool but at different speed or rates
of revolution settings due to the specific conditions present at
the various sites around the golf course. With prior art grass
treatment devices, this would require a number of grass treatment
tools each with an identical treatment head but with different
gearing, so as to perform the same treatment according to the
different rates and thereby achieve different types of
treatment.
[0011] It is possible with some prior art devices to, by misusing
the device, cause the treatment head to move at different rates.
Prior art devices are not generally configured to allow this, and
the results can be variable. Great damage can be caused to turf
surfaces from the misuse of such prior art equipment. In
particular, if a user is not skilled enough to operate the grass
treatment apparatus outside of its normal operating parameters, it
is still immensely difficult to instigate a specific and constant
treatment regime on a number of different portions of the golf
course using such an inaccurate way of adapting the treatment
characteristics of such prior art treatment devices.
[0012] The inventors, seeing the disadvantages associated with
prior art grass treatment devices and, in particular, the need for
several independent grass treatment devices to perform related but
different treatment operations, have derived a new solution to
these problems.
SUMMARY OF THE INVENTION
[0013] The inventors have sought to provide a grass treatment
device, which is capable of producing a different treatment effect
using a single treatment head by powering this treatment head at
variable numbers of revolutions per minute and torque levels, and
also by providing a single piece of apparatus for use with various
treatment heads, each of which requires powering at different
levels due to the different geometry and other characteristics
thereof.
[0014] The inventors have developed an interchangeable system
allowing the replacement of one grass treatment tool with another
with ease, wherein a first gear ratio may be unsuitable for both
types of tools, as the circumference of surface-engaging components
in these tools may vary significantly in some cases. Therefore, the
inventors have also sought to provide a variable speed transmission
suitable for use with a grass or turf treating apparatus.
[0015] Further, the inventors have sought to provide a propelled
grass treatment device, wherein the variable speed transmission can
further power device motion means of the propelled grass treatment
device at variable numbers of revolutions per minute and torque
levels.
[0016] According to a first aspect of the present invention there
is provided a grass treatment device, comprising: [0017] a motor
configured to provide a power; [0018] a grass treatment tool
configured to interact with and treat a grass surface; [0019] a
drive mechanism configured to propel the device relative to the
grass surface; [0020] a transmission operably positioned between
the motor, the tool and the drive mechanism, configured to transmit
power from the motor independently to the tool and to the drive
mechanism; [0021] wherein the transmission is further configured to
transform a constant output from the motor into independent
variable powering of the tool and the drive mechanism.
[0022] Preferably the drive mechanism configured to propel the
treatment device is powered by a different output shaft to that
operably connected to the grass treatment tool.
[0023] Preferably the drive mechanism configured to propel the
treatment device and the grass treatment tool are powered by
different transmission ratios. Alternatively the drive mechanism
configured to propel the treatment device and the grass treatment
tool are powered by the same gear box ratios.
[0024] Preferably the transmission is capable of providing a
continuously variable output. The transmission may comprise a
continuously variable transmission. Alternatively, the transmission
may comprise an infinitely variable transmission.
[0025] Preferably the transmission is capable of powering the grass
treatment tool at a plurality of speed settings. Preferably the
transmission comprises a speed selector mechanism.
[0026] Preferably the grass treatment device comprises a cassette
system configured to allow the introduction and removal of a
plurality of various grass treatment tools, each of which is
configured to be operably connected to the transmission.
[0027] Preferably the grass treatment tool is one selected from the
group comprising a vibratory roller; a thatchmaster; an ultra
grooma; a scarifier; a sarel roller cassette; a star spiker; a
rotary brush and a true level vibratory roller brush.
[0028] Preferably, the cassette system comprises a first and a
second roller configured to contact a grass surface, wherein the
treatment tool is positioned between the first and the second
roller.
[0029] Preferably the motor comprises an electrical motor.
Alternatively, the motor comprises an internal combustion
motor.
[0030] Preferably the grass treatment device is selected from the
group comprising two-wheeled, four-wheeled and tracked devices.
[0031] Preferably the grass treatment device is selected from the
group comprising devices requiring the user to stand in close
proximity thereto, devices requiring the user to sit thereon and
remote--controlled devices.
[0032] According to a second aspect of the present invention there
is provided a transmission suitable for use with a hand operated
grass treatment device, the device comprising: [0033] a motor
configured to provide power; [0034] a grass treatment tool
configured to interact with and treat a grass surface; [0035] a
drive mechanism configured to propel the device relative to the
grass surface; and [0036] the transmission; [0037] wherein the
transmission is operably positioned between the motor, the tool and
the drive mechanism, and is configured to transmit power from the
motor independently to the tool and to the drive mechanism; and
[0038] wherein the transmission is further configured to transform
a constant output from the motor into independent variable powering
of the tool and the drive mechanism.
[0039] According to a third aspect of the present invention, there
is provided a kit of parts for a grass treatment device,
comprising: [0040] a motor configured to provide power; [0041] a
grass treatment tool configured to interact with and treat a grass
surface; [0042] a drive mechanism configured to propel the device
relative to the grass surface; and [0043] a transmission operably
positioned between the motor, the tool and the drive mechanism,
configured to transmit power from the motor independently to the
tool and to the drive mechanism; [0044] wherein the transmission is
further configured to transform a constant output from the motor
into independent variable powering of the tool and the drive
mechanism.
[0045] According to a fourth aspect of the present invention, there
is provided a method of independently powering a drive mechanism
and a grass treatment tool of a grass treatment device, the method
comprising the steps of: [0046] providing the device with the grass
treatment tool, the drive mechanism and a motor; [0047] providing
the device with a transmission operably positioned between the
motor, the tool and the drive mechanism, wherein the transmission
is configured to transform a constant output from the motor into
independent variable powering of the tool and the drive mechanism;
and [0048] transmitting power from the motor independently to the
tool and to the drive mechanism through the transmission.
BRIEF DESCRIPTION OF THE DRAWINGS
[0049] For a better understanding of the invention and to show how
the same may be carried into effect, there will now be described by
way of example only, specific embodiments, methods and processes
according to the present invention with reference to the
accompanying drawings in which:
[0050] FIG. 1 provides a perspective view of a right side of a
grass treatment device according to a first embodiment of the
present invention, including a variable transmission having a first
linkage arrangement.
[0051] FIG. 2 provides a perspective view of a left side of the
grass treatment device of FIG. 1, including the variable
transmission having a second linkage arrangement.
[0052] FIG. 3 provides a perspective view of the variable
transmission of FIGS. 1 and 2, in isolation of the grass treatment
device, and including ratio selection levers.
[0053] FIG. 4 provides a side elevation of the ratio selection
lever of FIG. 3 connected to the first linkage arrangement of FIG.
1.
[0054] FIG. 5 provides a side elevation of the ratio selection
lever of FIG. 3 connected to the second linkage arrangement of FIG.
2.
[0055] FIG. 6 provides a side elevation of the ratio selection
lever of FIG. 3 connected to a linkage arrangement according to
another embodiment.
[0056] FIG. 7 provides a perspective view of two linkage
arrangements such as that show in FIG. 6, in isolation of the
transmission, one in respect of each of the tool speed gear ratio
and the device motion gear ratio.
DETAILED DESCRIPTION
[0057] There will now be described by way of example a specific
mode contemplated by the inventors. In the following description
numerous specific details are set forth in order to provide a
thorough understanding. It will be apparent however, to one skilled
in the art, that the present invention may be practiced without
limitation to these specific details. In other instances, well
known methods and structures have not been described in detail so
as not to unnecessarily obscure the description.
[0058] In accordance with a first specific embodiment of the
present invention and with reference to FIG. 1 herein, there is
shown a right perspective view of a grass treatment device 101, in
the example a hand mower. This hand mower is configured to interact
with and treat a grass surface over which it travels, by way of a
number of different grass treatment tools which it may carry and
power. It will be readily understood by the skilled person that the
principles of the present invention are not limited to the example
hand mower, and that the present invention is equally capable of
implementation in any other type of propelled grass treatment
device, whether it be two-wheeled, four-wheeled or tracked, and
whether it be of the type requiring the user to stand in close
proximity thereto, requiring the user to sit thereon, or
remote--controlled.
[0059] The hand mower 101 comprises several distinct components, or
sections. A first component is a user interface 102 for operating
the hand mower, specifically to direct the other components of the
hand mower in a required direction and/or at a required speed. The
user interface comprises device steering means 103, device speed
control means 104 and tool speed control means 105, which allow the
user of the hand mower 101 to comprehensively control operation of
the hand mower.
[0060] Further components of the hand mower comprise a power unit
or motor 106, a transmission or gear box 107 which is coupled with
the power unit or motor 106 at an input portion 108 thereof, and a
drive mechanism 109 to propel the mower 101, which is coupled with
the transmission 107 at a first output portion 110 thereof.
Transmission 107 and device speed control means 104 are connected
to one another by a first linkage arrangement 111, which will be
further detailed hereinafter.
[0061] With reference to FIG. 2 herein there is shown a left
perspective view of the grass treatment device 101 of FIG. 1,
wherein the transmission or gear box 107 is coupled with the power
unit or motor 106 at the input portion 108 thereof, and a further
component of the hand mower comprises a grass treatment head 112
housing a grass treatment tool (not shown), wherein the grass
treatment tool is coupled with the transmission 107 at a second
output portion 113 thereof. Transmission 107 and tool speed control
means 105 are connected to one another by a second linkage
arrangement 114, which will be further detailed hereinafter.
[0062] The treatment head 112 may comprise a cassette system, which
permits the introduction and removal of a plurality of various
grass treatment tools, each of which is configured to be operably
connected to the transmission 107 at the second output portion 113
thereof. Such a cassette system may comprise first and a second
rollers (not shown) configured to contact the grass surface over
which hand mower 101 travels, wherein the grass treatment tool is
positioned in a space located between the first and the second
rollers, whereby the rollers ably position the treatment tool such
that it can interact with e grass surface and perform the necessary
treatment tasks. Many different grass treatment tools may be used
by green keepers for maintaining turf surfaces, including: [0063]
the vertical cutter tool, which is used to prevent thatch
accumulation and cut through stolons and rhizomes in fine turf.
Regular use of the vertical cutter tool will improve surface
texture especially when used in conjunction with light
top-dressing. The Tungsten tipped blades are spaced at 10 mm
centers. [0064] the ultra groomer tool, which has 90 tungsten
carbide tipped blades spaced 5 mm apart, this tool ensures greens
turf is maintained in the best possible conditions. It helps
minimise puffiness in both high density creeping bent and Bermuda
grass and removes unsightly seed heads in Poa annua turf with
minimal treatment. On newly established greens, it can help reduce
the ingress of Poa annua by uprooting individual Poa plants before
they get a chance to take hold. [0065] the scarifier tool, for
greens that already have thatch at depth. The Scarifier tool
includes a plurality of super tough blades spaced at 45 mm apart,
spaced apart by brush spacers which ensure a hygienic clean-up and
effective throwing of the removed thatch into the grass catchers.
[0066] the sarel roller tool, for continual rolling whilst cutting,
the airborne silt generated therewith creating surface sealing on
fine turf. This can lead to decreased infiltration rates and a
reduction in gas exchange between the atmosphere and the root zone
upper horizon. Regular use of the sarel roller tool prevents
surface sealing with minimal surface disruption. [0067] the star
spiker tool, which is an alternative method of reducing surface
sealing, but uses the same principles as the sarel roller. [0068]
the rotary brush tool, the formation of which ensures that the
collection of debris is focused into the middle of the grass
catcher, thereby maximising the available volume. The bristles are
made from high quality nylon resulting in a durable brush with
"flex memory", with a plurality of different bristle stiffness
grades. [0069] the true level vibratory roller brush tool, which
permits the efficient integration of sand top-dressing deep into
the turf canopy. Even if the top-dressing sand is damp, integration
can be assisted by brushing and vibratory rolling simultaneously.
The Vibro Brush can also be used without vibration, by switching
off the drive to the Vibro Roller, thereby truning it into a static
brush.
[0070] With reference to FIG. 3 herein, there is shown a
perspective view of a casing 300, which encloses the variable
transmission or gear box suitable for use as a component 107 of the
grass treatment device 101 previously described, having a single
power input portion 108 and two independent output portions 110,
113.
[0071] In the preferred embodiment of the present invention,
transmission 107 is capable of providing a continuously variable
output, by changing through an infinitive number of effective gear
ratios between minimum and maximum values.
[0072] In a specific embodiment of the present invention,
transmission 107 is a continuously variable transmission (CVT). A
CVT is a transmission in which the ratio of the rotational speeds
of two shafts, such as the input shaft and output shaft of a
vehicle or other machine, can be varied continuously within a given
range, providing an infinite number of possible ratios. The CVT
comprises a plurality of arrangements of discs and rollers
transmitting power between the discs, wherein the power input shaft
301 at power input portion 108 receives power from motor 106 and is
operably connected to two respective arrangements of discs and
rollers, which are symmetrically disposed left and right relative
to the input shaft 301.
[0073] The transmission comprises an input sprocket, located on the
end of the input shaft 301. This input sprocket is operably
connected to a differential. Projecting from opposite edges of this
differential are respective transverse shafts. On a first side 302
of the transmission, power input shaft 301 is therefore operably
connected to a first transverse shaft. The transverse shaft bears a
disc tapering into a cone away from the input shaft 301, wherein
the longitudinal axis of the cone is coaxial with the transverse
shaft and the disc is centrally mounted on the shaft. First power
output shaft 303 at output portion 110 is co-axial with the
transverse shaft and bears a second disc tapering into a cone
towards the input shaft 301, wherein the longitudinal axis of the
cone is coaxial with the first power output shaft 303 and the
second disc is centrally mounted on the shaft. The first and second
discs may be substantially similar to one another and horizontally
opposed to one another. First power output shaft 303 may
hereinafter be referred to as drive output shaft 303.
[0074] In this arrangement, the first disc is equivalent to the
driving pulley of a conventional belt transmission and the second
disc is equivalent to the driven pulley thereof. Rollers or wheels
are located between the discs and transmit power from one disc to
the other, being equivalent to the belt in the aforementioned
conventional belt transmission. The wheels can rotate along two
axes, they spin on an horizontal axis and tilt in or out around a
vertical axis, wherein the horizontal axis is substantially
co-planar with the transverse shaft and the first power output
shaft 303, and the vertical axis is substantially perpendicular to
the input and output shafts 301, 303. This arrangement allows the
wheels to contact the discs in different areas: when the wheels
contact the first (driving) disc nearer the apex of the cone, they
contact the second (driven) disc nearer the rim thereof, resulting
in a reduction in speed and an increase in torque of the driven
disc. Alternatively, when the wheels contact the first (driving)
disc nearer the rim thereof, they then contact the second (driven)
disc nearer the center thereof, resulting in an increase in speed
and a decrease in torque. Therefore, tilting of the rollers or
wheels seamlessly changes the gear ratio of the transmission
between the first and second discs, occasioning smooth and
substantially instantaneous ratio changes.
[0075] The above arrangement constitutes a first respective
arrangement of discs and rollers, of the two arrangements
symmetrically disposed left and right relative to the input shaft
301, and it is suitable for transmitting power from motor 106 to
first power output shaft 303, in turn powering the drive mechanism
109.
[0076] A substantially identical arrangement of discs and rollers
constitutes the second respective arrangement of discs and rollers
of transmission 107, for independently transmitting power from
input shaft 301 to second output shaft 304 (hidden from view in
FIG. 3) at output portion 113, in order to power the grass
treatment tool located in head 112.
[0077] Therefore, on a second side 305 of the transmission, power
input shaft 301 is operably connected to a second transverse shaft,
for instance by way of the differential mechanism discussed above,
which likewise bears a disc tapering into a cone away from the
input shaft 301, wherein the longitudinal axis of the cone is
coaxial with the transverse shaft and the disc is centrally mounted
on the shaft. Second power output shaft 304 is co-axial with the
second transverse shaft and bears a further disc tapering into a
cone towards the input shaft 301, wherein the longitudinal axis of
the cone is coaxial with the first power output shaft 110 and the
second disc is centrally mounted on the shaft. Again, rollers or
wheels are located between the discs and transmit power from one
disc to the other, being equivalent to the belt in the
aforementioned conventional belt transmission. The wheels again can
rotate along two axes, they spin on an horizontal axis and tilt in
or out around a vertical axis, wherein the horizontal axis is
substantially co-planar with the transverse shaft and the second
power output shaft 304, and the vertical axis is substantially
perpendicular to the input and output shafts 301, 304. Therefore,
tilting of the rollers or wheels seamlessly changes the gear ratio
of the transmission between the first and second discs, occasioning
smooth and substantially instantaneous ratio changes for powering
second power output shaft 304, independently of the first
arrangement powering first power output shaft 303.
[0078] In a further specific embodiment of the present invention,
transmission 107 comprises a specific type of continuously variable
transmission (CVT), the infinitely variable transmission (IVT). In
this specific embodiment, the range of ratios of the speed of
output shafts 303, 304 to the speed of input shaft 301 includes a
zero ratio, i.e. a zero output shaft speed with a defined input
speed. This transmission type is achieved by combining the
continuously variable transmission detailed above with a planetary
gear system, also known as an epicyclic gear system, wherein the
gear system effectively translates the difference between two
speeds within the IVT transmission (for instance the speed of the
power input shaft 301 receiving power from the engine 106 and the
speed of the first power output shaft 303) into the actual output
shaft rotation speed. The present description does not purport to
provide a comprehensive explanation of continuously variable
transmissions and infinitely variable transmissions, which is
beyond the scope of the present description and is not required for
understanding the present invention.
[0079] In the preferred embodiment, and with reference to FIGS. 1
to 3, the transmission 107 is therefore operably positioned between
the motor 106, the drive mechanism 109 and the grass treatment tool
112, and is configured to transmit power from the motor 106 input
via input shaft 301 independently to the tool via output shaft 304
and to the drive mechanism via output shaft 303. The power output
from the motor 106 to input shaft 301 is constant, however the
independent control of the two discs and rollers arrangements
respectively on either side 302, 305 of transmission 107 permits a
selection of gear ratio for the grass treatment tool and the drive
mechanism independently of one another.
[0080] Independent transmission arrangements represent an important
advantage of the invention, because the combination of the device
speed with the tool RPM and torque levels define in part the
treatment effected by a specific tool unto the grass surface: the
same tool rotating at a constant rate affects a grass surface
differently if it is traveling at 3 miles per hour, rather than 5
miles per hour. Likewise, given a device traveling at a constant
speed, the tool affects a grass surface differently if it rotates
at 1500 rpm, rather than 2500 rpm. By providing devices in which
the drive means and the grass treatment means can be operated at
different respective speed, the functionality and versatility of
the device is improved.
[0081] In order to vary the transmission ratios, the transmission
further comprises CVT ratio selection levers 306, 307, which are
respectively configured to modulate the activity of the CVT discs
in the two arrangements of the transmission for modifying the
operation of either the drive mechanism driven by the drive output
shaft 303, or the grass treatment tool driven by the cutter output
shaft 304, or both. Each of ratio selection levers 306, 307 is
connected to the user interface 102 via a respective linkage
arrangement 111, 114.
[0082] With reference to FIG. 4, a first embodiment of the first
linkage arrangement 111 is shown, wherein the ratio selection lever
306 is pivotally connected to a device motion control link 401 at a
first end 402 thereof, and wherein a second end 404 of device
motion control link 401 is pivotally connected to a device motion
control arm 403. In FIGS. 4 and 5, the engine has been removed for
purposes of clarity, and would engage power input shaft 301 by way
of a clutch, only a first plate 400 of which is shown. The clutch
may for instance be a centrifugal clutch, configured to engage
shaft 301 once a set amount of rotations per minute is reached.
[0083] Device motion control arm 403 is pivoted by a first motion
control pivot 405 mounted to a portion of the transmission casing
300, proximal the motion control link end 404 at which it is
pivotally connected to device motion control link 401, whereby
device motion control arm 403 may pivot relative to motion control
pivot 405 independently of its pivotal connection to device motion
control link 401. This configuration permits a longitudinal
displacement of motion control link 401, relative to the pivoted
first and second ends 402, 404 thereof, therefore translating any
actuation of motion control arm 403 into a corresponding actuation
of the ratio selection lever 306.
[0084] Device motion control arm 403 is further connected to a
first motion control spring 406 extending between motion control
arm 403 and a cable housing bracket 407. Cable housing bracket 407
houses at least one motion control cable (not shown), which
operably links device motion control arm 403 to device speed
control means 104 of user interface 102, the spring 406 providing a
bias towards a position of device motion control arm 403 at which
the transmission has a neutral ratio.
[0085] Device motion control arm 403 is further articulated to a
motion control bracket 408 at a first end thereof. Motion control
bracket 408 is substantially centrally pivoted by a second motion
control pivot 409 mounted to another portion of the transmission
casing 300. Motion control bracket 408 comprises a reversing stop
bracket 410 at a second end thereof, which is connected to a second
motion control spring 411 extending between motion control bracket
408 and the cable housing bracket 407. The articulation between
motion control arm 403 and motion control bracket 408 is configured
to restrict the travel of device motion control arm 403 when
inputting a transmission ratio with device speed control means 104
of user interface 102, which is apt to effect reverse motion of the
device, the spring 411 providing a bias towards a position of
device motion control bracket 408 at which the transmission has a
neutral ratio.
[0086] Thus, actuation of device speed control means 104, in the
example a lever 104, imparts an amount of tension in at least one
motion control cable, which is translated into a forward or reverse
motion of motion control arm 403 relative to motion control pivot
405, any reverse motion of motion control arm 403 being subjected
to the travel restriction afforded by motion control bracket 407,
and which is translated into a corresponding compression or
expansion of either of respective motion control springs 406, 411,
as a function of whether the user wishes to displace the grass
treatment device forwards, or backwards, or bring it to a stop. The
motion of motion control arm 403 and, optionally, of motion control
bracket 407 relative to their respective pivots 405, 409, result in
a corresponding translation of motion control link 401, in turn
imparting a corresponding motion to ratio selection lever 306 at
which time the transmission ratio is changed, proportionally to the
actuation input of lever 104.
[0087] With reference to FIG. 5, a first embodiment of the second
linkage arrangement 114 is shown which is, in principle,
substantially similar to first linkage arrangement 111. Ratio
selection lever 307 is pivotally connected to a tool speed control
link 501 at a first end 502 thereof, and a second end 504 of tool
speed control link 501 is pivotally connected to a tool speed
control arm 503.
[0088] Tool speed control arm 503 is pivoted by a motion control
pivot 505 mounted to a portion of the transmission casing 300,
proximal the end 504 at which it is pivotally connected to tool
speed control link 501, whereby tool speed control arm 503 may
pivot relative to rotation control pivot 505 independently of its
pivotal connection to tool speed control link 501. This
configuration permits a longitudinal displacement of tool speed
control link 501, relative to the pivoted first and second ends
502, 504 thereof, therefore translating any actuation of tool speed
arm 503 into a corresponding actuation of the ratio selection lever
307.
[0089] Tool speed control arm 503 is further connected to a tool
speed control spring 506 extending between tool speed control arm
503 and a cable housing bracket 507. Cable housing bracket 507
houses at least one tool speed control cable (not shown), which
operably links tool speed control arm 503 to tool speed control
means 105 of user interface 102, the spring 506 providing a bias
towards a position of tool speed control arm 503 at which the
transmission has a neutral ratio.
[0090] Thus, actuation of tool speed control means 105, in the
example a lever 105, imparts an amount of tension in the at least
one tool speed control cable, which is translated into a forward or
reverse motion of tool speed control arm 503 relative to tool speed
control pivot 505, and which is translated into a corresponding
compression or expansion of tool speed control spring 506, as a
function of whether the user wishes to increase or decrease the
rotation speed of the grass treatment tool in head 112, or bring it
to a stop. The motion of tool speed control arm 503 relative to
pivot 505 results in a corresponding translation of motion control
link 401, in turn imparting a corresponding motion to ratio
selection lever 307, at which time the transmission ratio is
changed, proportionally to the actuation input of lever 105.
[0091] With reference to FIGS. 6 and 7, a further embodiment of the
second linkage arrangement 114 is shown, which comprises
substantially less components than the first embodiment and which
is therefore advantageous in terms of cost and maintenance,
relative to the first embodiment.
[0092] In this embodiment, the engine 106 is connected to the
transmission 107 by a centrifugal clutch 601. The engine idle speed
is preset to a certain number of revolutions per minute, in the
example it is factory set to approximately 1400 rpm. The clutch 601
is likewise preset to engage the first input shaft 301 at a certain
number of revolutions per minute, in the example it is adjusted to
approximately 1700 rpm.
[0093] A cable (not shown) links the tool speed control means 105
to the throttle on the engine 106, wherein actuation of the tool
speed control means 105 by the user increases or decreases the
engine rpm, whereby the transmission engages or disengages the
first input shaft 301 through the clutch, proportionally to the
input by the user.
[0094] The output from the transmission is dependent on the
position of a transmission adjusting lever 602. In the horizontal
position, the transmission adjusting lever 602 is in "geared
neutral", wherein there is no output from the transmission at
second output shaft 304, although the internals of the gearbox,
described with reference to FIG. 3, i.e. the discs, rollers and
shafts, are still rotating. A displacement of the transmission
adjusting lever 602 upwards relative to the horizontal position
proportionally increases the output from the gearbox at output
shaft 304. A displacement of the transmission adjusting lever 602
downwards relative to the horizontal position proportionally
reverses the output from the gearbox at output shaft 304.
[0095] Displacement of the transmission adjusting lever 602 is
effected by a lever adjustment assembly 603, which comprises a
transmission adjusting lever engaging shaft 604, a shaft height
adjusting knob 605 and a shaft bracket 606 affixed to the
transmission casing 300.
[0096] Transmission adjusting lever 602 is fixedly connected to the
engaging shaft 604, and at least a portion of the outer surface of
shaft 604 is threaded.
[0097] Shaft height adjusting knob 605 comprises a longitudinal
through hole 605A having an inner surface, at least a portion of
which comprises a thread suitable for engaging the thread of the
outer surface of shaft 604. A first portion 607 of the outer
surface of shaft height adjusting knob 605 has a first diameter and
a second portion 608 of the outer surface of shaft height adjusting
knob 605 has a second diameter larger than that of the first
portion.
[0098] Shaft bracket 606 is located substantially above, and is
substantially vertically relative to, the transmission adjusting
lever 602, and is longitudinally coaxial with both the transmission
adjusting lever engaging shaft 604 and the shaft height adjusting
knob 605. Shaft bracket 606 comprises a through hole 606A having a
diameter suitable for accommodating the first portion 607 of the
outer surface of shaft height adjusting knob 605, and is configured
to permit rotation of the shaft height adjusting knob 605 therein
without any longitudinal translation relative to the bracket
606.
[0099] As shaft height adjusting knob 605 rotates about the shaft
604 engaged in its longitudinal through hole by way of their
respective threads, and rotates coaxially with the through hole of
bracket 606 without any longitudinal translation relative thereto
along shaft 604, rotation of knob 605 therefore effects an upward
or downward translation of the shaft 604 relative to the
combination of the knob 605 and bracket 606. In the example,
turning the adjusting knob 605 in the clockwise direction displaces
the lever 602 in an upward manner and, reciprocally, turning the
adjusting knob 605 in the counter-clockwise direction displaces the
lever 602 in a downward manner. Advantageously, the second portion
608 of the outer surface of shaft height adjusting knob 605 may be
knurled, to improve user interaction therewith.
[0100] In a specific embodiment, the portion 609 of shaft 604 which
protrudes from the aperture in the adjusting knob 605 comprises
graduation means, in the example indentations, which are visible to
the user until such time as the downward translation of the shaft
604 relative to the combination of the knob 605 and bracket 606
within the knob through hole obscures them, therefore as a function
of the number of revolutions by which the knob 605 is turned. The
speed of the second output shaft 304 can therefore be correlated to
the graduation means, in the example the amount of graduated marks
which are visible.
[0101] It may be possible that errors are made when reading the
graduations means, depending on the user's viewpoint. In a further
specific embodiment, to reduce such errors, means are provided to
allow a user to adjust the height of the shaft 604, and therefore
the displacement of the transmission adjusting lever 602 relative
to its neutral horizontal position, by predetermined quantized
amounts only. Such adjusting means may comprise a ball detent, i.e.
a spring-biased ball, and at least one complementary depression,
which may be implemented at the rotatable connection between the
shaft height adjusting knob 605 and the bracket 606.
[0102] For instance, at least one depression may be implemented in
the outer surface of the first portion of knob 605, and a
complementary ball detent mechanism may be implemented at a fixed
position in the through hole of the bracket 606 accommodating the
first portion 607 of knob 605, the ball detent mechanism having a
longitudinal axis perpendicular to the longitudinal axis of the
shaft 604, knob 605 and bracket 606.
[0103] Preferably, a plurality of depressions may be disposed
radially about the outer surface of the first portion 607 of knob
605, and the ball of the ball detent is configured to releasably
lock with each of the plurality of depressions, whereby when the
user rotates the knob 605, a jolt is felt each time the ball in the
bracket 606 releasably locks into a depression on the outer surface
607 of the knob 605. As and when the user is satisfied that the
knob 605 has been sufficiently rotated to achieve the required tool
speed, the ball releasably locks into place in a depression of the
outer surface 607 of the knob 605. The strength of the biasing
means is sufficient to keep the ball locked into the depression
during normal use of the grass treatment device, and the ball can
only be released from the depression by further rotation of the
knob 605.
[0104] By careful selection of the outer radius of the outer shaft
of knob 605, the number of depression and the pitch of the
corresponding threads of the inner shaft 604 and threads of the
inner wall of the knob 605, the distance of linear movement of the
inner shaft 604 relative to the combination of knob 605 and bracket
606 can be related to the distance between depressions on the knob
605. By selecting a different diameter for the first portion 607 of
the outer surface of knob 605, or a different pitch of threads, or
a different number of depressions on the outer surface, the
predetermined quantized amount can be altered.
[0105] With reference to the description of FIGS. 4 and 5, the
first and second linkage arrangements, respectively for the first
portion of the transmission dedicated to motion of the device and
for the second portion of the transmission dedicated to powering of
the device tool, are functionally equivalent. In the same manner,
the principles described in relation to the further embodiment of
the second linkage arrangement 114 in FIG. 6 are applicable to the
first linkage arrangement 111. A first linkage arrangement 111
according to this further embodiment is substantially identical to
the second linkage arrangement 114 described in FIG. 6, therefore
as shown in FIG. 7, whereby again resulting in the capacity to
change the respective transmission ratios for the device motion and
the tool speed independently of one another, proportionally to user
input.
* * * * *